Copending Application Ser. No. 581,785, filed May 29, 1975 in the name of the present inventor, describes an energy storage system in which heat may be stored for prolonged periods of time so as to provide a continuous source of energy, even though the primary energy source which provides the primary heat to the system may be of an intermittent and variable nature. In the particular embodiment disclosed in the Copending Application, a wind operated electric generating unit is described as constituting the primary energy source.
The system forming the subject matter of the Copending Application includes, in one particular embodiment, a storage tank which is buried in the ground, and which contains a liquid with a higher boiling point that water and a sub-zero (Farenheit) freezing point. The liquid, for example, may be a solution of water and calcium chloride. When the liquid solution in the storage tank is heated, it has sufficient capacity to store enough heat to furnish electricity and heat for prolonged periods of time.
Heat may be derived from the liquid solution in the storage tank by circulating water or other liquid, through a coiled pipe in the solution. The water in the coiled pipe is thereby converted to a steam, and the resulting steam may be used directly for heating purposes, or it may be used to drive electric generators or the like, or furnish electricity on demand, or it may be used for other energy requirements.
The solar heat collector and storage system of the present invention uses an improved, simplified economical solar heat collector as source of heat energy, and the collector may be used, either alone, or in conjunction with another energy source, as the primary source of energy for a heat storage system, such as the system described in the Copending Application. However, it will become evident as the present description proceeds, that the solar heat collector of the invention may be used in a wide variety of present day solar heat systems.
A feature of the solar heat system of the invention is the provision of a solar heat collector that is constructed to cause the liquid to flow freely down the inclined roof of a building, fully exposed to the atmosphere, so as to absorb heat from the sun rays during its travels. The heat collector used in the system of the invention, unlike the prior art collectors, is simple and inexpensive, and it does not require the multiplicity of components which are incorporated into the present day prior art solar energy collectors.